1. Field of the Invention
The present invention relates to the manufacture of packing paper which has a good capacity for printing. It aims principally at providing papers for fields of application where such a property is required without correlatively excellent mechanical properties being required.
2. Background Discussion
So-called top of the line papers are known which have a very good surface state, good capacity for printing and high mechanical resistance characteristics. For example, these are papers intended for written printing using offset or helio. In addition, papers are known whose surface state is slightly homogeneous, whose mechanical properties are high and which, at the same time, have a low capacity for printing. These are, for example, papers of the kraft paper type which are intended for use as various types of packing, in particular carrier boxes.
The papers used in packing are printed using flexography. In accordance with this method, ink is brought to a plate by means of a cylinder, with the plate in turn serving to print the paper. In this type of method, it can happen that the ink migrates into the paper instead of remaining on the surface, which causes dimensional instability of the paper and leads to a poor print reproduction. In general, this characteristic is not harmful for the applications for which it is used.
However, in the field of packing or of covering cardboard boxes, in particular, it is desirable to present packing which is pleasant to look at so as to further attract the attention of the clientele. It has been noted that a white packing which is adorned with printed designs is particularly appreciated. To achieve this result, a good print reproduction of the packing is necessary. However, a paper used in such an application need not necessarily have exceptional mechanical characteristics. For example, as applications, advertising display units for food products, by which it is sought to capture the attention of the customers, can be cited. However, the only products presently available in the packing market are those indicated previously, of the writing print type paper, which are particularly expensive. Papers which have both a very good surface state, a good capacity for printing and low mechanical properties, while retaining a white color, are not presently known.